Successful long-term cryopreservation of neonatal rat islet tissue.

Neonatal rat pancreatic tissue was frozen to -196 degrees C using Me2SO as a cryoprotectant and a slow freezing rate to -70 degrees C followed by immersion in liquid nitrogen. Rapid thawing was used. Viability was demonstrated by successful transplantation to streptozotocin-induced diabetic recipients. Long-term preservation, up to 4 weeks, did not demonstrably affect viability. Cryopreservation techniques may afford a method for providing a diabetic recipient the opportunity to receive a large quantity of pooled islet tissue from well-matched donors.